On Sun, 2010-07-11 at 17:21 +0200, Arnout Engelen wrote:
> On Sun, Jul 11, 2010 at 04:53:14PM +0200, Ralf Mardorf wrote:
> > today I compared a default Ubuntu Studio with and without the
> > proprietary NVIDIA driver.
>
> OK, so the proprietary driver seems to yield better 'worst latency' values
> compared to nouveau. That's kind of odd, anything X-related would have a much
> lower priority than the MIDI threads.
>
> > Note that for Ubuntu Studio 2 tests failed because of time out errors
>
> What exactly timed out?
There was a time out message by the alsa-midi-latency-test. It started
and than it asked, if there still is a connection, while there still was
a connection.
>
> > even the tests that were passed with success are significantly less good,
> > than the tests with openSUSE, were I set up audio myself.
> >
> > What might be the difference between Ubuntu and Suse?
>
> > ------------------------------------------------------------------------
> > Ubuntu Studio 10.04 amd64
> > 2 x Terratec EWX 24/96 (2 single cards, but 1 virtual card)
> > Frequency scaling ?
> > ------------------------------------------------------------------------
> > spinymouse@email-addr-hidden:~$ uname -a
> > Linux ubuntu 2.6.32-23-preempt #37-Ubuntu SMP PREEMPT Fri Jun 11
> > 10:19:07 UTC 2010 x86_64 GNU/Linux
> > spinymouse@email-addr-hidden:~$ envy24control
> > 0xcf00, irq 20, Master Clock int 44100
>
> > ------------------------------------------------------------------------
> > openSUSE 11.2 amd64
> > 2 x Terratec EWX 24/96 (2 single cards, but 1 virtual card)
> > Frequency scaling performance
> > ------------------------------------------------------------------------
> > spinymouse11.2@email-addr-hidden-2:~> uname -a
> > Linux suse11-2 2.6.31.6-rt19 #1 SMP PREEMPT RT Wed Nov 18 16:59:26 CET
> > 2009 x86_64 x86_64 x86_64 GNU/Linux
>
> 2 differences jump out:
>
> - the frequency scaling is set to 'performance' on your suse install and to
> '?' on your ubuntu install.
Yes, I assume that an audio distro won't start with ondemand by default,
I'll run hwinfo to see the scaling next time. For Ubuntu Studio there
are a lot of issues that are nwe to me, no xorg.conf, no menu.lst etc..
> - The kernel options for your suse install has the options 'SMP PREEMPT RT',
> while your ubuntu install has the options 'SMP PREEMPT'. In other words, it
> looks like your ubuntu kernel has 'normal' preemption, but not the -rt
> patch.
I didn't noticed that, you're right. The Suse kernel is self build, the
Ubuntu Studio kernel is from the repositories.
> The latter looks like a good candidate for explaining the difference. Could
> you test with the kernel from the linux-image-2.6.31-10-rt package instead of
> the kernel from the linux-image-2.6.32-21-preempt package which you seem to be
> using now?
Thank you, a good idea, before I'll build a kernel by myself, it would
take around 50 minutes, I'll install this kernel from the repository.
To be continued.
Ralf
>
>
> Kind regards,
>
> Arnout
_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev@email-addr-hidden
http://lists.linuxaudio.org/listinfo/linux-audio-dev
Received on Sun Jul 11 20:15:06 2010
This archive was generated by hypermail 2.1.8 : Sun Jul 11 2010 - 20:15:06 EEST